I usually ride on M424s, which are similar but with more grip on the cage. I'd recommend those or the alloy-cage equivalent if you're thinking along these lines. They're definitely OK with normal shoes.
I didn't want SPD one-side/platform the other: as an SPD novice I was going to be fiddling about enough without getting the pedal the right way up, but I also wanted to be able to jump on the bike in trainers/sandals for short distances -- maybe slower, maybe not very comfortable, but without my feet sliding off. These pedals do all that. They're fine in reasonably thick-soled normal shoes though you can feel the cleat.
I wanted to be able to walk in my riding shoes which restricted my choice of shoes, and meant I had to file off a grippy bit of the pedal (I now also ride platforms in my SPD shoes as part of a bike-train-bike commute).
Also I avoid clipping in when I'm carrying my daughter in a toddler seat (or I unclip well in advance of anything that might make me put my foot down). By being able to pedal unclipped even in SPD shoes (axle under the arch of my foot, so not exactly efficient) I can drop her off then carry on riding.
It was a real bonus having them recently. I did a long ride (for me: 48 miles/4 hours including stops) and being able to unclip and still pedal lightly helped when cramp was threatening.
But for family holidays, when I don't even take the SPD shoes, and have my daughter on the back more often than not, I swap to platform pedals.